A Max Fleischer Superman cartoon, made in the fantastic style that would be copied (to a degree) later in the various DC animated stories.
In this one, a group of masked thugs decide to rob a gold train. Of course, Lois Lane is also riding on the train, giving Superman a reason to care. And of course, once the thugs realize who their dealing with, do they do the sensible thing and head for the hills? No. They try shooting him.
You'd think villains would have a newsletter or something where they could pass along these tips: bullets don't hurt Superman.
Anyway, a lot of fun, and some great retro animation.